A display device is described in DE 10 2004 016 808 A1, in which the windscreen of a motor vehicle serves as the display screen. In this conventional display device, display elements are distributed over a significant fraction of the vehicle windscreen, to each of which light is directed via a waveguide associated with a light source arranged at the edge of the windscreen. To ensure that the light from such a light source actually reaches the eyes of the driver of the motor vehicle, it must be diffused in the display elements. The display elements should not obstruct the driver's vision when they are not lit. Therefore, they should include structures that are small enough to be invisible to the human eye when they are not lit.
However, such structures affect ambient light in the same way as they do to the light from the light source, that is to say they scatter it. Accordingly, the windscreen inevitably appears cloudy to the operator at the sites where display elements are located. The more brightly the display element is intended to appear for a given illumination strength from the light source, in other words, the more densely the light-scattering structures are positioned, the more pronounced the cloudiness appears. In order to ensure that the display element is clearly visible while minimizing the clouding of the windscreen, the density with which the light-scattering structures are positioned must be low, and the light source that illuminates the display element must emit correspondingly more light. This leads to increased energy consumption and distracting light reflections can also occur at the edges of the windscreen if a large proportion of the light is propagated through the windscreen without being diffused to the outside by a display element.